lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

x86, asm: Introduce and use percpu_inc()

Browse Source 
... generating slightly smaller code.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <4BCF261F020000780003B33C@vpn.id2.novell.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
Jan Beulich
2010-04-21 15:21:51 +01:00
committed by H. Peter Anvin
parent 1d16b0f2f3
commit 402af0d7c6
3 changed files with 27 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

24
arch/x86/include/asm/percpu.h
View File

@@ -190,6 +190,29 @@ do { \
pfo_ret__; \
})
#define percpu_unary_op(op, var) \
({ \
switch (sizeof(var)) { \
case 1: \
asm(op "b "__percpu_arg(0) \
: "+m" (var)); \
break; \
case 2: \
asm(op "w "__percpu_arg(0) \
: "+m" (var)); \
break; \
case 4: \
asm(op "l "__percpu_arg(0) \
: "+m" (var)); \
break; \
case 8: \
asm(op "q "__percpu_arg(0) \
: "+m" (var)); \
break; \
default: __bad_percpu_size(); \
} \
})
/*
* percpu_read() makes gcc load the percpu variable every time it is
* accessed while percpu_read_stable() allows the value to be cached.
@@ -207,6 +230,7 @@ do { \
#define percpu_and(var, val) percpu_to_op("and", var, val)
#define percpu_or(var, val) percpu_to_op("or", var, val)
#define percpu_xor(var, val) percpu_to_op("xor", var, val)
#define percpu_inc(var) percpu_unary_op("inc", var)
#define __this_cpu_read_1(pcp) percpu_from_op("mov", (pcp), "m"(pcp))
#define __this_cpu_read_2(pcp) percpu_from_op("mov", (pcp), "m"(pcp))